Water conservation is becoming increasingly important as the cost of treating domestic water increases and sources of clean feedstock become scarce. In most domestic households treated domestic water is used to flush toilets. This is a waste of a valuable commodity. It also increases the cost of sewage treatment charged to the home owner because the municipal cost of sewage treatment is largely based on the amount of domestic water consumed. Furthermore, solar energy is not effectively used as a means to heat domestic water as it remains expensive to purchase and install the components. Therefore, fresh cold water is sent to the hot water heater requiring significant amounts of thermal energy to bring it to a desired temperature. Rainwater is a source of toilet flush water that is often overlooked.
A number of attempts have been made to solve the problem of conserving domestic water. For example, U.S. Pat. No. 4,228,006 “Domestic Water System” issued to Hanna on Oct. 14, 1980 discloses a system whereby grey water from various in-home sources is directed to a clarifier. Chlorine is added. The water is then reused for non-potable applications. Hanna relies upon the addition of toxic chemicals and does not utilize solar energy for heating. The use of rain water is over looked by Hanna. In U.S. Pat. No. 5,406,657 “Water Recycling Device for Flush Toilet Use” issued to Donati on Apr. 18, 1995 there is disclosed the use of grey water to supply the toilet tank with flushing water. This system can be retrofitted into existing domestic plumbing systems. The Donati system relies upon an external pond to collect rain water. This source can become easily contaminated and turbid and is not suitable for pumping through domestic household pipes. Another example is found in U.S. Pat. No. 6,889,395 “Flush Reservoir” issued to Hodges on May 10, 2005. Hodges discloses a rain water collection system for toilet flushing. However, no grey water is used.
Therefore, there continues to be a need for an integrated domestic utility system that uses both grey water recycling and rainwater to satisfy demands for non-potable water in a house, for example, toilet flushing. There is a further need for an integrated domestic utility system that takes advantage of available solar energy to maintain a readily available source of grey water at a suitable temperature for indoor use.